1. Field
The present general inventive concept described herein relates to a nonvolatile memory device and a method of improving program efficiency of the nonvolatile memory device.
2. Description of the Related Art
A semiconductor memory device may be volatile (hereinafter, referred to as a volatile memory device) or nonvolatile (hereinafter, referred to as a nonvolatile memory device).
Nonvolatile memory devices may include a mask read-only memory (MROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), etc.
A flash memory device may be a typical nonvolatile memory device. The flash memory device may have a cell string structure. A cell string may include a string selection transistor connected with a string selection line, memory cells connected respectively with word lines, and a ground selection transistor connected with a ground selection line. The string selection transistor may be connected with a bit line, and the ground selection transistor may be connected with a common source line.
At a read operation and a verification read operation, a pre-charge time may become longer as a result of a coupling capacitance among bit lines.